Definition of Thyroid

1. Hyperthyroidism Slideshow Pictures
2. Take the Thyroid Disorder Quiz
3. Thyroid Symptoms and Solutions Slideshow Pictures

Thyroid: 1. The thyroid gland. Also, pertaining to the thyroid gland. 2. A preparation of the thyroid gland used to treat hypothyroidism. 3. Shaped like a shield. (The thyroid gland was so-named by Thomas Wharton in 1656 because it was shaped like an ancient Greek shield.)